The CBLL1 Knockout Jurkat Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population of the Jurkat T lymphoblast cell line with target-gene disruption in CBLL1. Following transient expression of Cas9 and a CBLL1-specific guide RNA, the edited cells are selected to create a heterogeneous knockout pool. This product offers a ready-to-use loss-of-function model that retains polyclonal diversity, avoiding clonal artifacts often associated with single-cell-derived lines.
The parental Jurkat cell line was derived from the peripheral blood of a 14-year-old male with acute T-cell leukemia and serves as a model for T-cell receptor (TCR) signaling and apoptosis. Its well-characterized signaling cascades and genetic tractability make it ideal for studying regulators of T-cell activation. Jurkat cells are extensively used to investigate pathways downstream of the TCR/CD3 complex and co-stimulatory receptors.
CBLL1, or Cbl-b, is a RING-type E3 ubiquitin ligase that negatively regulates TCR and growth factor signaling by targeting substrates for ubiquitin-mediated proteasomal degradation. It is activated downstream of the TCR/CD3 complex and CD28, and interacts with adaptors GRB2 and CIN85/SH3KBP1. Key targets include PI3K, PLC??1, and VAV1, whose ubiquitination attenuates AKT, mTOR, and NF-??B pathways, limiting IL-2 production. Representative pathway components upstream of CBLL1 include ZAP70, LAT, and SLP-76, while NFAT acts downstream.
In Jurkat cells, CBLL1 knockout removes this inhibitory checkpoint, leading to hyperphosphorylation of AKT (Ser473) and ERK, enhanced calcium flux, and elevated IL-2 secretion upon TCR engagement. The response threshold is lowered, and CD28 co-stimulation becomes less essential, mimicking a state of reduced anergy susceptibility. This phenotype renders the cells highly useful for studying the molecular underpinnings of autoimmunity and for exploring strategies to potentiate T-cell activity.
Applications include investigation of T-cell activation and anergy, autoimmunity and transplant rejection studies, cancer immunotherapy research, E3 ligase substrate profiling, and high-throughput screening for ubiquitination modulators. Typical assays involve flow cytometric measurement of CD69 and CD25, ELISA for IL-2, Western blotting for phospho-AKT and phospho-ERK, in vitro ubiquitination assays, CFSE proliferation assays, and NF-??B luciferase reporters. For further details, please contact Ascent Research.
